importing WordPerfect text into VP 10

I have both VP8 and VP10 and find that if I import text from wp5.x to VP10, it contains too many font codes, i.e., specifying typeface every time there is a change such as normal to ital. This does not happen w/ VP8. Is there a way to avoid this problem? I've been starting my import into VP8 on one machine, then when the project hits a significant stage, import the VP8 file into VP10 on a different terminal, avoiding the problem but requiring obvious extra steps.